Dakota Access pipeline will be built "subject to terms and conditions negotiated by us," he said.

Trump said the two projects will create many steelworkers jobs as his government will insist the pipes used in the projects be built in the United States.

Keystone XL project was rejected by former President Barack Obama in November 2015 because Democrats and environmental groups say it could worsen climate change by enabling further growth from the oil sands, which create higher greenhouse gas emissions than some other forms of production.

The project, worth 8 billion U.S. dollars, is proposed to go from Canada through the U.S. state of Montana and South Dakota to Nebraska, where it would connect with existing pipelines to carry more than 800,000 barrels of crude oil a day to refineries along the U.S. Gulf Coast.

The 3.8-billion-dollar Dakota Access pipeline begins in the Bakken oil fields in North Dakota and go southeast to Illinois.

It has caused strong protests in North Dakota near the Standing Rock Indian Reservation, as local tribes worried the project will pollute their drinking water and cultural sites, making the Department of Army agree to explore alternate routes in December.

Trump's executive order aroused a lot of criticism from environmental groups.

"Trump ignores tribal history and heritage, will of the people, and the climate crisis with today's announcement," said Sierra Club in a statement.

"More people sent comments against Dakota Access and Keystone XL to the government than any project in history," said Bill McKibben, co-founder of 350.org, an organization aiming to push forward global climate movement.

"Donald Trump ignores all that in his eagerness to serve the oil industry. It's a dark day for reason, but we will continue the fight," said McKibben.

However, Trump's decision has earned a warm welcome from U.S. oil and natural gas industry.

"Critical energy infrastructure projects like the Keystone XL and the Dakota Access pipelines will help deliver energy to American consumers and business safely and efficiently," Jack Gerard, president and CEO of the American Petroleum Institute, said in a statement.